1. Field
The claimed invention relates to communications of computer networks. More specifically, it relates to a method and system for prepaid billing for wireless mobile services in communications networks.
2. Description of Related Art
In legacy prepaid billing scenarios, control of user access to the network is performed by elements of the Signaling System 7 (SS7) network. To enable such services, wired networks have adopted te advanced intelligent network (xe2x80x9cAINxe2x80x9d) approach. The AIN approach provides for centrally located call control information and call processing logic, including the logic for prepaid billing, and a set of standardized messages between the network elements for accessing and using prepaid services, among other things.
Wireless telecommunications networks have been developed on a similar model. In some legacy wireless networks, the switching of calls and the signaling for call control may be performed by mobile switching centers (MSCs). Each MSC typically controls one or more base stations or base transceiver stations (BTSs), sometimes via one or more base station controllers (MSCs). Each BTS provides a wireless coverage area within which wireless mobile nodes, such as mobile phones, personal digital/data assistants, and other mobile devices, can communicate with the BTS over an air interface. Alternatively, the functions of the MSC may be integrated into or integral to the BSC, thereby eliminating the MSC. In such case, the functions performed by the MSC may be performed by one or more BSCs.
Each wireless mobile node typically has a xe2x80x9chomexe2x80x9d wireless network in which a home location register (HLR) serves as a centralized repository of information about the wireless mobile node. Typically, the HLR contains a user profile for the wireless mobile node, the last reported location of the mobile station, and the current status of the mobile station, such as whether it is active or inactive. The user profile may also contain indications or attributes of the enhanced services to which the wireless mobile node subscribes. Further, the user profile may be cataloged by the Mobile Identification Number (MIN), the dialed number, the Mobile Directory Number (MDN), the wireless mobile node""s unique 32-bit Electronic Serial Number (ESN), or any other wireless mobile node identifier.
When an MSC (or alternatively a BSC) needs to find information about a wireless mobile node, such as where it is located or what services it subscribes to, it queries the HLR corresponding to that wireless mobile node. Thus, to inquire about a wireless mobile node prepaid services, the MSC or BSC queries the HLR.
In a manner analogous to the AIN approach used in wireline networks, an MSC or a BSC may also query a Wireless Intelligent Network (xe2x80x9cWINxe2x80x9d) device for call processing instructions, in the course of either originating a call from or terminating a call to the wireless mobile node. Such queries can arise from trigger points set by the wireless mobile node""s service profile that the MSC or BSC downloaded from the wireless mobile node""s HLR. Moreover, the MSC or BSC use such queries to obtain the call processing instructions needed to provide enhanced telecommunications services to the wireless mobile node. In response to such queries, the WIN network devices will typically execute the appropriate service logic and consult the wireless mobile node""s service profile to formulate the call processing instructions that the WIN network devices then send to the MSC.
This is acceptable for voice services since-the Home Location Register (HLR) controls authorization of voice services. Units of use in the voice networks are typically time-based. And since voice activity inherently involves the SS7 network, the draw down of the usage units is reported to the HLR on a regular basis, which can provide for reasonable accounting of the usage.
Today, second generation (xe2x80x9c2Gxe2x80x9d) networks provide communication services to mobile nodes. These 2G networks have their foundation in older circuit-switched or packet-switched technologies that make the transmission of video and data quite slow, and thus, limit the type of multimedia, video and data services that can be used. In addition to the 2G networks, newer second-and-a-half generation (xe2x80x9c2.5Gxe2x80x9d) network services are currently providing communication services to mobile nodes. These 2.5G networks use newer packet-switched services, which allow for increased transmission speeds for video and data as compared to 2G networks. Like the 2G networks, current 2.5G networks have similar limitations on the types of multimedia, video, and data services that can be used.
Mobile nodes may take advantage of third generation (xe2x80x9c3Gxe2x80x9d) network services, which allow for significantly faster data rates that in turn allow for a broader range of multimedia, video and data services to be used on a roaming mobile node. The 3G networks provide packet switched services with the capability of providing Internet Protocol traffic, such as Mobile Internet Protocol (xe2x80x9cMobile IPxe2x80x9d) traffic; symmetrical and asymmetrical data rates; multimedia services such as video conferencing and streaming video; international roaming among different 3G operating environments; and more. Typical 3G systems include packet-based transmission of digitized voice, data and video. 3G networks encompass a range of wireless technologies such as Code Division Multiple Access (xe2x80x9cCDMAxe2x80x9d), Universal Mobile Telecommunications Service (xe2x80x9cUMTSxe2x80x9d), Wide-band CDMA (xe2x80x9cWCDMAxe2x80x9d), and others.
In 3G networks, communications originating and terminating from mobile nodes may use Mobile IP to establish a voice, video and/or data call from a mobile node that has roamed from its home network to a foreign network. Mobile IP allows mobile nodes to transparently move between different Internet Protocol sub-networks (xe2x80x9csubnetsxe2x80x9d). For a mobile node to use the services of the network, it has to connect to its home subnet. The home subnet provides access to an external network, such as the Internet, through a xe2x80x9chome agentxe2x80x9d that serves as the subnet""s gateway router.
To register on the 3G network, the mobile node may periodically transmit xe2x80x9cagent solicitationxe2x80x9d messages to the home agent. The mobile node also listens for xe2x80x9cagent advertisementxe2x80x9d messages from the PDSN. When a mobile node receives an agent advertisement message it registers with the PDSN that sent the agent advertisement message.
To provide services to the mobile node when the mobile node xe2x80x9croams,xe2x80x9d (i.e., dynamically changes its physical location), the mobile node periodically transmits xe2x80x9cagent solicitationxe2x80x9d messages to other gateway routers, and also listens for xe2x80x9cagent advertisementxe2x80x9d messages from the other gateway routers. When a mobile node receives an agent advertisement message indicating that it is now on a foreign subnet, it registers with the foreign gateway router or xe2x80x9cforeign agent,xe2x80x9d and with its home agent. The registration with the foreign agent allows the mobile node to receive data on the foreign subnet. Whereas, the concurrent registration with the home agent provides an indication to the home subnet that the mobile node is not at home. This may allow for forwarding to the foreign subnet the data directed to the mobile node received on its home subnet.
As noted above, 2G and later networks provide packet data services in addition to the current voice services. Further, migration of voice services to a Voice over IP model complicates matters because the packet data network may and most likely will become the carrier for voice traffic, in contrast to the current circuit based mechanism, where voice traffic is controlled by SS7 and/or Wireless Intelligent Network (WIN) elements.
However, there are several problems associated with establishing voice, video or data calls on 3G networks. One problem is that users currently cannot easily buy, use or replenish prepaid services, such as pre-paid calling accounts on mobile nodes some 3G networks. Such problems occur when legacy billing systems do not work on 3G networks, or the provider of the 3G networks access will not undertake providing 3G services to high-risk users. Further, without prepaid billing systems, large delays in receiving payments and/or bills can result in suspension or discontinuation of a user""s 3G network services. And after fees are paid, it may be difficult for users of mobile nodes on to re-establish service, when pre-paid billing systems are not implemented.
Moreover, without prepaid billing system in 3G networks, providers may have difficulty in disconnecting active users of mobile nodes when outstanding fees are owed. This difficulty is further complicated when the active users of the mobile nodes are constantly roaming from one foreign network to another because usage on each of the foreign networks may not be reported until a later date. In such case, it is possible for a user to overuse the amount of allotted network services. Conversely, users may be overcharged for actual usage if multiple network elements charger for the same service. While the aforementioned issues are common to both the data and voice services, the growth of data services and the demand for prepaid services in global markets will result in a need to satisfy these deficiencies.
Packet data traffic in the 3G networks are typically served to wireless mobile nodes by a Packet Data Serving Node (xe2x80x9cPDSNxe2x80x9d). The PDSN provides the same type of call control responsibility in the packet data network that the HLR provides in the circuit voice WINs network. Unlike the HLR, however, for the mobile nodes that it serves, packet data traffic may pass through the PDSN. Being in the packet-data-traffic path allows the PDSN to directly monitor and measure the usage of the wireless prepaid service. The PDSN need not be in the packet-data-traffic path, however, because the PDSN may receive usage information from another PDSN over a PDSN to PDSN link. Further details regarding inter-PDSN transfer are provided by co-pending U.S. application Ser. No. 10/097796, filed on Mar. 14, 2002, and titled xe2x80x9cMethod and System for Re-Direction and hand-off for Pre-Paid Mobile Services in Third Generation Networks,xe2x80x9d which is fully incorporated herein by reference.
Current 3G network models presently suffer from having (i) no mechanism for tracking the consumption or usage of prepaid wireless services in near real time (e.g., most systems have monthly bill reconciliation); (ii) no mechanism for varying the measurement unit (in near real time) for the type of data, (e.g., time units for voice services and/or byte units for data services); (iii) no mechanism for scaling the usage measurement unit (in near real time) on foreign or brokered networks to provide xe2x80x9cmarking-upxe2x80x9d or discounting of services when on a brokered network or foreign network; and (iv) inadequate mechanisms for conveniently handing-off an ongoing communication session.
Thus, it is desirable to provide a method and system to support prepaid accounting and billing services that work correctly with mobile nodes on 3G networks.
According to one embodiment, a method for providing roaming and hand-off support for prepaid billing for wireless prepaid services on a data network for wireless prepaid services may be carried out by a first-network-access device, such as a PDSN, carrying on session activity of a wireless communication session with a wireless mobile node within a first coverage area. A second-network-access device establishes connectivity with the wireless mobile node after the wireless mobile node moves into the second-network-access device""s coverage area. In response to moving into the coverage area of the second-network access device, the first-network-access device tunnels the session activity to the second-network-access device.
Before and after tunneling the session activity, the first-network-access device receives from a network-access-control device one or more block of credits, which may be drawn from a user account having a cache of available credits. Each of these blocks of credits may be all of the credits or less than all of the credits in the cache of available credits.
In addition, the first-network-access device may also receive one or more measurement-method parameters with each block of credits. These measurement-method parameters may include an indication for determining the usage units for the wireless communication session.
After receiving a block of credits and the measurement-method parameters, the network-access device periodically measures usage of the session activity for the wireless communication session. The first-network-access device may measure the usage of the session activity while the wireless mobile node is in the first coverage area in terms of a first of the measurement-method parameters. Additionally, the first-network-access device may measure the usage of the session activity tunneled to the second-network-access device in terms of a second of the measurement-method parameters. The first of the measurement-method parameters, however, may be the same as the second of the measurement-method parameters.
While session activity is ongoing, the first-network-access device debits the usage of the session activity from the blocks of credits. While the credits in the received blocks remain above a predetermined threshold, the first-network-access device may continue to debit the session activity from the blocks of credits.
In another embodiment, the first-network-access device carries on or engages in session activity for a wireless communication session with a wireless mobile node within a first coverage area. The first-network-access device receives from the network-access-control device one or more blocks of credits, which may be drawn from a user account having a cache of available credits. Each of these blocks of credits may be all of the credits or less than all of the credits in the cache of available credits.
In addition, the first-network-access device may also receive one or more measurement-method parameters with each block of credits. These measurement-method parameters may include an indication for determining the usage units for the wireless communication session.
After receiving a block of credits and the measurement-method parameters, the first-network-access device periodically measures usage of the session activity for the wireless communication session. The first-network-access device may measure the usage of the session activity while in the first coverage area in terms of a first of the measurement-method parameters.
While session activity is ongoing, the first-network-access device debits the usage of the session activity from the blocks of credits. While the credits in the received blocks remain above a predetermined threshold, the first-network-access device may continue to debit the session activity from the blocks of credits.
Sometime during the wireless communication session, but after the wireless mobile node moves into a second coverage area, a second-network-access device requests network access from the network-access-control device for the session activity of the wireless communication session. After receiving network access, the second-network-access device establishes the session activity for the wireless communication session. While the mobile node operates in the second coverage area, the second-network-access device receives from the network-access-control device one or more blocks of credits.
In addition, the second-network-access device may also receive one or more measurement-method parameters with each block of credits. Like the measurement-method parameters received by the first-network-access device, if any, these parameters the may include an indication for determining the usage units for the wireless communication session.
After receiving a block of credits and measurement-method parameters, the second-network-access device periodically measures usage of the session activity for the wireless communication session. The second-network-access device may measure the usage of the session activity while the wireless mobile node is in the second coverage area in terms of a second of the measurement-method parameters, which may differ from the first of the measurement-method parameters. The first of the measurement-method parameters, however, may be the same as the second of the measurement-method parameters.
The second-network-access device debits the usage of the session activity from the blocks of credits it receives. The second-network-access device may continue to debit the session activity from the blocks of credits while the credits in the received blocks remain above a predetermined threshold.
After the second-network-access device establishes the session activity for the wireless communication session, the first-network-access device may receive from the network-access-control device a first indication that causes the first-network-access device to stop debiting the usage of the session activity from the blocks of credits. This indication may be, for example, a stop accounting message, or a terminate session activity message.
The first-network-access device may also receive from the network-access-control device a second indication that causes the first-network-access device to return any remaining (i.e., unused) credits to the network-access-control device. These unused credits may be returned to the cache of available credits or reallocated to the session activity on the second-network-access device or any other eligible session activity.
Alternatively, after the second-network-access device establishes the session activity for the wireless communication session, the first-network-access device may request from the network-access-control device an additional block of credits. In response, the first-network-access device receives from the network-access-control device another indication that causes the first-network-access device to stop debiting the usage of the session activity from the first block of credits, and/or return any remaining credits to the network-access-control device. As before, these remaining credits may be returned to the cache of available credits or reallocated to the session activity on the second-network-access device or any other eligible session activity.
In another alternative, the first-network-access device may not receive from the network-access-control device a responsive indication to the request for additional block of credits. Without the responsive indication and upon expiry of remaining credits, session activity on the first-network-access device may terminate. In yet another alternative, when the first-network-access device does not receive from the network-access-control device a responsive indication to the request for additional block of credits, it may terminate the session activity, and return any unused credits to the network-access-control device.
In another embodiment, the first-network-access device carries on session activity of a wireless communication session with a wireless mobile node within a first coverage area. The first-network-access device receives from a network-access-control device one or more blocks of credits, which may be drawn from a user account having a cache of available credits. Each of these blocks of credits may be all of the credits or less than all of the credits in the cache of available credits.
In addition, the first-network-access device may also receive one or more measurement-method parameters with each block of credits. These measurement-method parameters may include an indication for determining the usage units for the wireless communication session.
After receiving a block of credits and the measurement-method parameters, the first-network-access device periodically measures usage of the session activity for the wireless communication session. The first-network-access device may measure the usage of the session activity while in the first coverage area in terms of a first of the measurement-method parameters.
While session activity is ongoing, the first-network-access device debits the usage of the session activity from the blocks of credits. The first-network-access device may continue to debit the session activity from the blocks of credits while the credits in the received blocks remain above a predetermined threshold.
Sometime during the wireless communication session, but after the wireless mobile node moves into a second coverage area, a second-network-access device establishes connectivity with the wireless mobile node. In response, the first-network-access device tunnels the session activity and any unused credits to the second-network-access device.
In addition, the second-network-access device may also receive from the first-network-access device one or more measurement-method parameters with each block of credits. Like the measurement-method parameters received by the first-network-access device, if any, these parameters the may include an indication for determining the usage units for the wireless communication session.
After receiving the tunneled credits, tunneled measurement-method parameters, and tunneled session activity, the second-network-access device periodically measures usage of the tunneled session activity for the wireless communication session. The second-network-access device may measure the usage of the tunneled session activity while in the second coverage area in terms of a second of the tunneled measurement-method parameters, which may differ from the first of the measurement-method parameters. The first of the measurement-method parameters, however, may be the same as the second of the tunneled measurement-method parameters. While in the second coverage area, the second-network-access device debits the usage of the tunneled session activity from the tunneled unused credits.
The second-network-access device may request network access from the network-access-control device for the session activity of the wireless communication session during a state transition in the session activity or at any other time. After receiving network access, the second-network-access device establishes independent network access for the session activity. In addition to receiving independent network access for the tunneled session activity, the second-network-access device receives from the network-access-control device one or more blocks of credits. The second-network-access device may also receive one or more measurement-method parameters with each block of credits. These measurement-method parameters received may include an indication for determining the usage units for the wireless communication session.
Thereafter, the second-network-access device periodically measures the usage of the session activity. The second-network-access device may measure the usage of the session activity after establishing independent network access in terms of a third of the measurement-method parameters, which may, but need not, differ from the first and the second of the measurement-method parameters.
The second-network-access device debits the usage of the session activity from the blocks of credits it receives. The second-network-access device may continue to debit the session activity from the blocks of credits while the credits in the received blocks remain above a predetermined threshold.
After the second-network-access device establishes independent network access, the first-network-access device may receive from the network-access-control device a first indication, such as a terminate session activity message, that causes the first-network-access device to stop debiting the usage of the session activity from the first block of credits, and/or that causes the first-network-access device to return any remaining (i.e., unused) credits to the network-access-control device. These unused credits may be returned to the cache of available credits or reallocated to the session activity on the second-network-access device or any other eligible session activity.
In a preferred embodiment, the first network-access device is carrying on session activity for a wireless communication session with a mobile node. The first network-access device has been allocated a block of credits by the network-access-control device. The mobile node roams to a second coverage area and initiates a session with a second network-access device. The second network-access device requests from the network-access-control device network access to support handoff activity of the wireless communications session. The network-access-control device retrieves from the first network-access device at least some of any remaining credits, then grants a new block of credits to the second network-access device. If desired, the first network-access device may also terminate its session in combination with its return of the remaining credits.
These as well as other embodiments will become apparent to those of ordinary skill in the art by reading the following detailed description, with appropriate reference to the accompanying drawings.